"Forfeit" by Dick Francis [UNABRIDGED AUDIOBOOK WITH TEXT]
James Tyrone, a racing reporter for a London scandal sheet, knew that fellow reporter Bert Chekov was a drunk, but he had always been an honest one. But when Bert dies in an "accidental" fall, Tyrone suspects a clue to his death might be found in columns Bert had written touting can't-lose race horses... horses that mysteriously failed to show up on race day.